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What are the differences between B trees and B+ trees?
...es are linked, so doing a full scan of all objects in a tree requires just one linear pass through all the leaf nodes. A B tree, on the other hand, would require a traversal of every level in the tree. This full-tree traversal will likely involve more cache misses than the linear traversal of B+ lea...
Unique Key constraints for multiple columns in Entity Framework
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@JJS - I got it to work where one of the properties was a foreign key.. by any chance is your key a varchar or nvarchar? There is a limit to the length of which can be used as a unique key.. stackoverflow.com/questions/2863993/…
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How to change line-ending settings
... a good idea to keep a .gitattributes file as we don't want to expect everyone in our team set their config. This file should keep in repo's root path and if exist one, git will respect it.
* text=auto
This will treat all files as text files and convert to OS's line ending on checkout and back to L...
Delegates: Predicate vs. Action vs. Func
Can someone provide a good explanation (hopefully with examples) of these 3 most important delegates:
8 Answers
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Elegant Python function to convert CamelCase to snake_case?
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For one instance, sure it's overkill. Across a larger application, no need to reinvent and obfuscate the wheel.
– Brad Koch
Dec 21 '15 at 22:47
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Spring Boot - Cannot determine embedded database driver class for database type NONE
...t;version>1.3.156</version>
</dependency>
But as mentioned in comments, the embedded H2 database keeps data in memory and doesn't stores it permanently.
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get keys of json-object in JavaScript [duplicate]
...o support IE8 or earlier (!), and B) If you did, you wouldn't do it with a one-off you wrote yourself or grabbed from an SO answer (and probably shouldn't have in 2011, either). You'd use a curated polyfill, possibly from es5-shim or via a transpiler like Babel that can be configured to include poly...
Best practices to test protected methods with PHPUnit
... So here, you would have to test the protected method (But never a private one). The solution to this, is to create a subclass for testing purpose, and use this to expose the methods. Eg.:
class Foo {
protected function stuff() {
// secret stuff, you want to test
}
}
class SubFoo extends F...
How to check if a Constraint exists in Sql server?
...nding other "constraints" here are some other queries for that:
--Returns one row for each CHECK, UNIQUE, PRIMARY KEY, and/or FOREIGN KEY
SELECT *
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
WHERE CONSTRAINT_NAME='XYZ'
--Returns one row for each FOREIGN KEY constrain
SELECT *
FROM I...
When should I use a NoSQL database instead of a relational database? Is it okay to use both on the s
... lot about them lately, but I'm still unsure why I would want to implement one, and under what circumstances I would want to use one.
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